An educational introduction
What is a brain tumour?
A brain tumour is an abnormal collection of cells in or near the brain. Some tumours are benign, meaning they do not behave like cancer, while others are malignant and may grow into nearby tissue or spread from another part of the body.
This page explains general concepts. Symptoms can have many causes, and only a qualified healthcare professional can assess an individual concern or recommend treatment.
Types of brain tumours
Classification begins with where a tumour started. A primary tumour begins in the brain or nearby structures. A secondary, or metastatic, tumour begins elsewhere in the body and later reaches the brain.
Primary tumours
These can develop from brain cells, the membranes around the brain, nerve-supporting cells, glands, or other local tissues. Gliomas, meningiomas, pituitary tumours, and schwannomas are examples of groups clinicians may consider.
Secondary tumours
These are cancers that have spread to the brain from another site. Their features and treatment are considered alongside the original cancer and the areas affected.
Gliomas and supporting cells
Gliomas arise from glial cells, which support and maintain the nervous system. Different glioma types can behave differently, so specialists use imaging, examination, and sometimes tissue analysis to identify the most appropriate classification.
Other primary tumours include ependymomas, pituitary tumours, germ-cell tumours, schwannomas, lymphomas of the central nervous system, and craniopharyngiomas. Their behaviour varies; a tumour’s location and size can matter even when it is not cancerous.
Possible symptoms
Symptoms depend on the tumour’s size, growth pattern, and location. They may also be caused by pressure on nearby structures or changes in how the brain works. Possible signs include:
- Headache that is new, persistent, or different from usual
- Nausea or vomiting, particularly alongside other neurological changes
- Changes in vision, hearing, speech, movement, or balance
- Seizures in someone who has not experienced them before
- Weakness, numbness, clumsiness, or difficulty walking
- Changes in memory, concentration, behaviour, or alertness
These symptoms are not specific to brain tumours. A sudden, severe, or rapidly worsening symptom should be treated as urgent and assessed by local emergency services.
Pituitary tumour symptoms
Tumours near the pituitary gland may affect hormone signals or vision. Possible effects include changes in body growth, menstrual cycles, sexual function, weight, thirst, temperature tolerance, or peripheral vision. The pattern depends on the hormones involved and the tumour’s pressure on nearby structures.
How diagnosis works
Assessment usually begins with a medical history and neurological examination. A clinician may check movement, strength, coordination, sensation, memory, speech, eye movements, and responses to light. The next steps depend on the findings and the person’s wider health.
MRI and CT
MRI uses magnetic fields and radio waves to produce detailed images. CT uses X-rays to create cross-sectional images and may be useful when speed or bone detail is important.
Biopsy and laboratory study
When appropriate and safe, a sample may be examined to identify the tumour type, grade, and likely behaviour. Not every tumour requires the same testing pathway.
Other investigations can include specialist eye tests, blood tests, hormone assessment, or imaging of blood vessels. The medical team chooses tests according to the suspected diagnosis and the information needed for planning care.
Treatment approaches
Treatment is individualised. Decisions may take account of the tumour type, grade, size, position, symptoms, overall health, and the person’s preferences. A specialist team may recommend one approach or a combination.
- Surgery: removal or sampling when this can be done safely.
- Radiotherapy: carefully targeted radiation used in selected situations.
- Drug treatment: medicines such as chemotherapy or other tumour-specific treatments when appropriate.
- Monitoring: regular scans and reviews for some slow-growing or low-risk tumours.
- Rehabilitation: physical, occupational, or speech therapy when symptoms affect movement, communication, or daily activities.
Common questions
Does every brain tumour mean cancer?
No. Some tumours are benign and do not spread, although their size or location can still cause important problems. Malignant tumours can invade tissue or behave more aggressively.
Can symptoms alone identify a tumour?
No. Many common conditions can cause headaches, dizziness, fatigue, or changes in concentration. Diagnosis requires clinical assessment and, where indicated, appropriate testing.
Why are scans used?
Scans help show the tumour’s location, size, and relationship with nearby structures. MRI and CT provide different kinds of information, so clinicians select the most useful examination.
Is surgery always needed?
No. Some tumours can be monitored or treated with other methods. Surgery is considered when its expected benefits outweigh its risks and when obtaining tissue or removing tumour is appropriate.
Where can I find general brain anatomy guides?
Brain Made Simple’s central nervous system, cerebral cortex, and brainstem guides provide background reading.